Leaked documents have revealed the UK government's plans for the days and weeks that will follow the death of Queen Elizabeth II.
The plans, codenamed Operation London Bridge, outline how news of the 95-year-old's death will be delivered to the British public and how official social media accounts will be managed.
While reports about the operation have circulated for years, the documents seen by Politico news website are the most detailed yet to filter into the public domain.
Following the queen's death, there will be a “call cascade” as the prime minister, cabinet secretary and ministers become the first people outside the British royal family to be informed.
The royal family's website will change to a black holding page, while a short statement will be released to confirm the monarch's death, according to the leaked document.
The banners on UK government websites will also change to black.
According to the step-by-step plans, the day of the queen's death will be "D-Day" – with each day afterwards leading up to her funeral known as D+1, D+2 etc.
They also outline how the queen's funeral will be held at Westminster Abbey, in central London, 10 days after her death.
Her son and heir Prince Charles will tour England, Scotland, Wales and Northern Ireland – which together make up the UK – in the lead-up.
The papers also reveal that the queen will lie in state for three days at the Houses of Parliament and that a day of mourning will be declared for her funeral.
A funeral service will take place in St George’s Chapel at Windsor Castle, a royal residence in southern England.
The burial will take place at the castle’s King George VI Memorial Chapel, where the queen's husband Prince Philip was laid to rest in April this year.
The queen remains in good health but it is understood that the plans were altered by the outbreak of the coronavirus pandemic.
A memo seen by Politico revealed official concerns that the funeral could put enormous strain on London's emergency services.
It is expected that millions of people would flock to the streets of the capital to witness the historic event.
Buckingham Palace has declined to comment on the leak or the plans.
The queen has reigned since 1952.
